A method for real-time monitoring of internal temperature of rock during microwave-induced cracking

Abstract

The application provides a real-time monitoring method for rock internal temperature during microwave cracking, and relates to the technical field of temperature measurement. The method first calibrates the optical fiber temperature coefficient based on an infrared camera; then prepares a rock sample with a heating hole, sets a measuring hole in the rock sample, and places the optical fiber in the temperature measuring hole, pours and blocks the measuring hole; then places the coaxial radiator into the heating hole; starts the microwave equipment, heats the rock to a preset time; when the microwave equipment starts to display the microwave power indication, the optical fiber is scanned by a demodulator, and the data is continuously scanned and saved during the microwave heating, so that the real-time monitoring of the rock hole temperature is realized. The method is completely not interfered by the microwave field, solves the problem that the temperature is not accurately measured due to the interference of the microwave field on the sensor, and realizes the real-time monitoring of the rock internal temperature under the strong microwave field.

Description

Technical Field

[0001] This invention relates to the field of temperature measurement technology, and in particular to a method for real-time monitoring of the internal temperature of rocks during microwave-induced fracturing. Background Technology

[0002] When light propagates in an optical fiber, scattering occurs. If the intensity of the scattered light changes while the frequency remains constant, this type of scattering is called elastic scattering, or Rayleigh scattering. If both the scattered light and its frequency change, this type of scattering is called inelastic scattering, including Raman scattering and Brillouin scattering. Since the scattering parameters are related to temperature changes, the temperature change can be calculated from the changes in these parameters, and the location of the relevant scattering points can also be determined. Based on these principles, researchers have developed distributed optical fiber temperature measurement technologies: distributed optical fiber temperature measurement based on Rayleigh scattering, distributed optical fiber temperature measurement based on Brillouin scattering, and distributed optical fiber temperature measurement based on Raman scattering. Optical fiber temperature measurement technology overcomes the shortcomings of traditional point-type electrical temperature sensors, offering advantages such as strong resistance to electromagnetic interference, long monitoring distance, low cost, and long lifespan. It is widely used in various applications, including fire alarm warning, oil and gas pipeline leak monitoring, high-voltage transmission cable safety monitoring, and subway tunnel temperature monitoring.

[0003] During the excavation of deep-buried hard rock underground engineering projects, the sudden release of elastic energy accumulated in the rock mass is frequently encountered, causing dynamic phenomena such as large-scale rock bursting, ejection, and shoving, i.e., rock bursts, which pose a great hazard to construction equipment and workers. Constructing stress relief holes at the tunnel face and in the tunnel walls creates a stress-reducing zone, which can release the elastic energy of the surrounding rock in advance, effectively reducing the stress concentration in the surrounding rock and decreasing the intensity and frequency of rock bursts. Using microwave pre-splitting technology can improve the stress relief effect of pre-drilling and can well adapt to working conditions that traditional stress relief methods cannot handle. Compared with traditional heating technology, microwave heating is a volumetric heating method, meaning that it heats the rock simultaneously and differentially within a certain depth range. Within this range, the temperature changes rapidly and the temperature difference is large, making thermal fracturing more effective. When conducting microwave heating stress relief tests in rock boreholes in the laboratory, it is necessary to study the influencing factors (stress, temperature, etc.) and laws of microwave heating stress relief to guide engineering practice.

[0004] Because microwaves are electromagnetic waves, they generate strong electromagnetic fields during microwave heating experiments, significantly interfering with electrical sensors. This makes it difficult to accurately measure temperature using electrical sensors, and the measured temperatures are only those at a single point. While infrared thermography can be used to monitor the surface temperature of rocks in real time during surface heating, it is difficult to monitor the temperature inside the rock borehole. Current temperature measurement methods are insufficient for monitoring the internal temperature of rocks during microwave heating inside boreholes. Therefore, there is an urgent need for a real-time monitoring method for the internal temperature of rocks during microwave heating experiments inside boreholes, accurately capturing temperature changes during the process and ensuring experimental safety. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for real-time monitoring of the internal temperature of rock during microwave fracturing, thereby achieving real-time monitoring of the internal temperature of the borehole during microwave fracturing of hard rock.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for real-time monitoring of the internal temperature of rock during microwave-induced fracturing, involving a coaxial radiator, microwave equipment, demodulator, optical fiber, and a rock sample with heating holes. The specific monitoring method is as follows:

[0007] Calibrating the temperature coefficient of optical fiber using an infrared camera;

[0008] Prepare a rock sample with a heating hole, set a measuring hole in the rock sample, and place an optical fiber in the measuring hole;

[0009] Pour and seal the measuring hole;

[0010] Place the coaxial radiator into the heating hole;

[0011] Start the microwave equipment and heat the rock for the preset time. When the microwave equipment starts to display the microwave power reading, use a demodulator to scan the optical fiber. During microwave heating, scan and save data continuously to achieve real-time monitoring of the temperature inside the rock borehole.

[0012] Preferably, the specific method for calibrating the fiber temperature coefficient based on an infrared camera is as follows:

[0013] Step S1: Prepare the complete rock sample, electromagnetic shielding material, computer, demodulator, infrared camera, optical fiber, shielding frame, shielding box, rectangular waveguide and surface radiator required for the calibration test, and determine the microwave power and heating time;

[0014] Step S2: Connect the shielding box to the shielding frame, and place the infrared camera inside the shielding box to prevent microwave interference with the infrared camera; adjust the field of view of the infrared camera by changing the position of the shielding box to ensure that the microwave radiating surface is within the field of view of the infrared camera; mark the fiber optic temperature measurement section according to the size of the rock sample, and select an appropriate position on the surface of the rock sample to fix the fiber optic cable, which should be within the field of view of the infrared camera; extend the fiber optic cable out of the shielding frame and fix it to the ground; after the fiber optic cable is installed, connect one end of the rectangular waveguide to the microwave equipment and the other end to the surface radiator, with the surface radiator close to the rock surface to ensure that the infrared camera can monitor the rock surface temperature through the shielding box;

[0015] Step S3: Fix the optical fiber, keeping it under slight tension, while ensuring that the optical fiber is in close contact with the rock sample surface; ensure that the optical fiber in the temperature measurement area is free from external obstructions, so that the infrared camera and the optical fiber can simultaneously monitor the surface temperature of the rock in the same area.

[0016] Step S4: Calibrate the demodulator, connect the optical fiber to the demodulator, check and record the temperature coefficient of the optical fiber at this time; connect the infrared camera to the computer, and use the infrared camera to record the initial temperature of the rock surface; perform microwave heating, and the infrared camera and optical fiber simultaneously monitor the temperature change at the same location.

[0017] Step S5: Data processing, compare the temperature monitored by the infrared camera with the temperature change of the optical fiber at the same time and location, and correct the temperature coefficient;

[0018] Step S6: Input the new temperature coefficient obtained in step S4 into the demodulator, and repeat the microwave heating experiment of steps S2-S4 n times. Compare the new temperature coefficients obtained in the n experiments. When the fluctuation of the new temperature coefficient is less than the set threshold, input the new temperature coefficient as the final fiber temperature coefficient into the demodulator.

[0019] Preferably, the specific method of step S5 is as follows:

[0020] The temperature changes of both the infrared camera and the optical fiber at the same time were plotted using graphing software. The infrared monitoring temperature at different locations was divided by the optical fiber monitoring temperature, and the average of the results was calculated to obtain the optical fiber temperature correction coefficient. The optical fiber temperature correction coefficient was multiplied by the optical fiber monitoring temperature to obtain the corrected optical fiber monitoring temperature. The corrected optical fiber monitoring temperature was compared with the infrared monitoring temperature. When the temperature difference between the two methods at the same location does not exceed a set threshold range, the temperature overlap at that location is considered good. When the proportion of temperature points with good overlap exceeds the set threshold, the temperature correction coefficient is considered accurate. The temperature correction coefficient is then multiplied by the original optical fiber temperature coefficient to obtain the new temperature coefficient.

[0021] Preferably, the measuring hole is located near the heating hole, and the diameter of the measuring hole is between 1 and 1.5 cm, while keeping the wall of the measuring hole smooth.

[0022] Preferably, the method further includes an optical fiber fixing tube installed on the side near the heating hole. The fixing tube is hollow, and the optical fiber is installed under the fixing tube to avoid the optical fiber being squeezed by the thermal deformation of the rock during the temperature measurement process.

[0023] Preferably, the fixing tube is composed of an arc-shaped tube and a soft plastic sheet, and the arc-shaped tube and the soft plastic sheet are bonded together; an electromagnetic shielding material is provided on the fixing tube to prevent microwaves from passing through the fixing tube from another direction and heating the rock; the soft plastic sheet is connected to the wall of the measuring hole to prevent the fixing tube from moving.

[0024] Preferably, the method involves pouring mortar into the measuring hole and sealing the measuring hole from the front with electromagnetic shielding material.

[0025] Preferably, the method further detects whether the optical fiber is faulty before monitoring the temperature; the optical fiber is installed on the demodulator, and the demodulator is used to repeatedly scan the optical fiber in the absence of a heat source. If the temperature change curve is close to 0, it means that there is no temperature change; otherwise, the optical fiber is faulty; the horizontal coordinate of the end of the optical fiber is recorded. During the installation of the optical fiber, the optical fiber is continuously scanned. When the horizontal coordinate of the end of the optical fiber changes, it indicates that the optical fiber has broken.

[0026] Preferably, the rock sample size is greater than twice the microwave penetration depth inside it.

[0027] The beneficial effects of adopting the above technical solution are as follows: The method for real-time monitoring of the internal temperature of rock during microwave fracturing provided by the present invention is completely unaffected by microwave field interference, which solves the problem of inaccurate temperature measurement caused by microwave field interference of previous sensors, and realizes real-time monitoring of the internal temperature of rock under strong microwave field. Attached Figure Description

[0028] Figure 1 A flowchart of a method for real-time monitoring of the internal temperature of rock during microwave fracturing, provided as an embodiment of the present invention;

[0029] Figure 2 A diagram showing the layout of the test equipment for calibrating the temperature coefficient of optical fibers, provided in an embodiment of the present invention.

[0030] Figure 3 A comparison of temperature monitored by an infrared camera and by an optical fiber over a period of 3 minutes, provided in an embodiment of the present invention;

[0031] Figure 4 This is a schematic diagram of the internal temperature test of rock during microwave borehole heating provided in an embodiment of the present invention;

[0032] Figure 5 This is a schematic diagram of the installation of the optical fiber in the measuring hole according to an embodiment of the present invention;

[0033] Figure 6 A schematic diagram of the optical fiber fixing tube provided in an embodiment of the present invention;

[0034] Figure 7 A schematic diagram of the internal temperature distribution of rock monitored by optical fiber according to an embodiment of the present invention;

[0035] In the diagram, 1. Computer, 2. Demodulator, 3. Fiber optic cable, 4. Shielding frame, 5. Rock sample, 6. Infrared camera, 7. Rectangular waveguide, 8. Surface radiator, 9. Coaxial radiator, 10. Mortar filling body, 11. Fiber optic fixing tube, 12. Heating hole, 13. Tin foil, 14. Measuring hole, 15. Curved tube, 16. Soft plastic sheet. Detailed Implementation

[0036] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0037] In this embodiment, a method for real-time monitoring of the internal temperature of rock during microwave-induced fracturing is described, such as... Figure 1 As shown, it includes the following steps:

[0038] Step 1: Calibrate the fiber temperature coefficient; Based on the principle of fiber optic temperature measurement, the fiber temperature coefficient needs to be input into the demodulator. However, the temperature coefficient differs for each type of fiber, therefore, it is necessary to calibrate the fiber temperature coefficient under a strong microwave field. Using the temperature monitored by an infrared camera as a benchmark (accuracy 0.01℃), compare the temperature changes of the infrared camera and the fiber at the same time and location, thereby calibrating the fiber temperature coefficient.

[0039] Step 1.1: Prepare the following for the calibration test: complete rock sample (5), tin foil (13), computer (1), demodulator (2), infrared camera (6), optical fiber (3), shielding frame (4), shielding box, rectangular waveguide (7), and surface radiator (8). Determine the microwave power and heating time. The optical fiber temperature coefficient calibration test setup is as follows: Figure 2 As shown;

[0040] Step 1.2: Connect the shielding box to the shielding frame 4, and place the infrared camera 6 inside the shielding box to prevent microwave interference with the infrared camera 6; adjust the field of view of the infrared camera 6 by changing the position of the shielding box to ensure that the microwave radiation surface is within the field of view of the infrared camera 6; mark the fiber optic temperature measurement section according to the size of the rock sample 5, and select an appropriate position on the surface of the rock sample to fix the fiber optic cable 3. This position should be within the field of view of the infrared camera 6; extend the fiber optic cable 3 outside the shielding frame 4 and fix it to the ground to prevent it from bending at a large angle, shaking, or slipping during the test; after the fiber optic cable 3 is installed, connect one end of the rectangular waveguide 7 to the microwave equipment and the other end to the surface radiator 8. The surface radiator 8 is close to the rock surface, at a distance of about 5-7 cm. This distance ensures that the infrared camera 6 can monitor the rock surface temperature through the shielding box.

[0041] Step 1.3: Use tin foil 13 to fix the optical fiber 3 at multiple points, keeping the optical fiber 3 in a slightly taut state. At the same time, repeatedly press the tin foil 13 to ensure that the optical fiber 3 is in tight contact with the surface of the rock sample 5. The optical fiber 3 in the temperature measurement area is not obstructed by any external objects, so that the infrared camera 6 and the optical fiber 3 can monitor the surface temperature of the rock in the same area at the same time.

[0042] Step 1.3: Calibrate demodulator 2, connect fiber optic cable 3 to demodulator 2, check and record the fiber optic temperature coefficient at this time; connect infrared camera 6 to computer 1, and use infrared camera 6 to record the initial temperature of the rock surface; after electromagnetic shielding is done and the microwave equipment is checked for water supply, microwave heating can be started, and infrared camera 6 and fiber optic cable 3 will monitor the temperature change at the same location at the same time.

[0043] Step 1.4: Data processing. Compare the temperature changes monitored by infrared camera 6 and fiber optic 3 at the same time and location. Use plotting software to plot the temperature changes of both infrared camera 6 and fiber optic 3 at the same time. Divide the infrared monitoring temperature at different locations by the fiber optic monitoring temperature, and average the results to obtain the fiber optic temperature correction coefficient. Multiply the fiber optic temperature correction coefficient by the fiber optic monitoring temperature to obtain the corrected fiber optic monitoring temperature. Compare the corrected fiber optic monitoring temperature with the infrared monitoring temperature. When the temperature difference between the two methods at the same location does not exceed the set threshold range of ±3℃, the temperature overlap at that location is considered good. When the proportion of temperature points with good overlap exceeds the set threshold of 90%, the temperature correction coefficient is considered accurate. Multiply the temperature correction coefficient by the original temperature coefficient of the fiber optic cable to obtain the new temperature coefficient. For example, when heating with a microwave power of 2kW for 5 minutes, the temperature coefficient of the fiber optic cable can be determined based on the two temperatures. Figure 3 As shown, the corrected temperature coefficient is 0.6709;

[0044] Step 1.5: Input the new temperature coefficient obtained in step 1.4 into demodulator 2, and repeat the microwave heating experiment in steps 1.2-1.4 n times. Compare the new temperature coefficients obtained in the n experiments. When the fluctuation of the new temperature coefficient is less than the set threshold, input the new temperature coefficient as the final fiber temperature coefficient into the demodulator.

[0045] Step 2: Prepare a rock sample with heating hole 12. The sample size should be greater than twice the microwave penetration depth inside it, such as... Figure 4 As shown;

[0046] Step 3: In order to measure the internal temperature of the rock, a small-diameter measuring hole 14 needs to be set near the heating hole 12, and the optical fiber 3 is installed in the measuring hole 14. In order to ensure the accuracy of the internal temperature measurement, the diameter of the measuring hole 14 is between 1-1.5cm, and the wall of the measuring hole 14 is kept smooth.

[0047] Step 4: According to the principle of fiber optic temperature measurement, the accuracy of fiber optic temperature measurement is affected by deformation. A fiber optic fixing tube 11 is fabricated, and the fiber optic cable is installed under the fixing tube 11. The fixing tube 11 is hollow and can withstand a certain amount of pressure, preventing the fiber optic cable from being squeezed by the thermal deformation of the rock during temperature measurement. Figure 5As shown; the fixing tube 11 is composed of an arc-shaped tube 15 and a soft plastic sheet 16, and the arc-shaped tube 15 and the soft plastic sheet 16 are connected by high-temperature adhesive, as shown. Figure 6 As shown; aluminum foil is placed on the fixed tube 11 to prevent microwaves from passing through the fixed tube from another direction and heating the rock;

[0048] Step 5: Install the fixing tube 11; apply high-temperature adhesive to the soft plastic sheet to connect the soft plastic sheet to the wall of the measuring hole and prevent the fixing tube from moving; the fixing tube is installed on the side close to the heating hole. For example, when the measuring hole is located above the heating hole, the fixing tube is inserted into the measuring hole along the bottom of the hole; when the measuring hole is located near the bottom of the heating hole, the fixing plate is inserted into the measuring hole along the top of the hole.

[0049] Step 6: Check if the optical fiber is faulty; install the optical fiber onto demodulator 2, and repeatedly scan the optical fiber with demodulator 2 in the absence of a heat source. If the temperature change curve is close to 0, it means there is no temperature change; otherwise, the optical fiber is faulty; record the x-coordinate of the end of the optical fiber. During the installation of the optical fiber, scan the optical fiber continuously. When the x-coordinate of the end of the optical fiber changes, it indicates that the optical fiber has broken.

[0050] Step 7: Install the optical fiber; Apply adhesive high-temperature glue to the optical fiber, insert it into the measuring hole along the bottom of the fixing tube, pull the optical fiber taut to make it in close contact with the wall of the measuring hole; after the optical fiber is installed, gently pull the optical fiber. If it does not move, the installation is complete.

[0051] Step 8: Pour the measuring hole; Pour the measuring hole with mortar, and prevent a large amount of mortar from entering the fixed pipe during the pouring process; After pouring, place the sample at room temperature for at least 24 hours.

[0052] Step 9: Seal the measuring hole; use tin foil to seal the measuring hole from the front to prevent microwaves from entering the mortar filler 10 inside the measuring hole;

[0053] Step 10: Install the specimen; Align the coaxial radiator 9 with the heating hole 12 on the rock specimen, and slowly move the coaxial radiator 9 into the heating hole 12;

[0054] Step 11: Use tin foil to make electromagnetic shielding, start the microwave equipment, and heat the rock for the preset time; when the microwave power reading begins to be displayed, use demodulator 2 to scan the optical fiber for the first time, and continuously scan and save data during microwave heating;

[0055] Step 12: After the experiment, clean up the equipment and process the data. The internal temperature of the rock is as follows: Figure 7 As shown.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope defined by the claims of the present invention.

Claims

1. A method for real-time monitoring of the internal temperature of rock during microwave-induced fracturing, comprising a coaxial radiator, microwave equipment, demodulator, optical fiber, and a rock sample with heating holes, characterized in that: Calibrating the temperature coefficient of optical fiber using an infrared camera; Prepare a rock sample with a heating hole, set a measuring hole in the rock sample, and place an optical fiber in the measuring hole; Pour and seal the measuring hole; Place the coaxial radiator into the heating hole; Start the microwave equipment and heat the rock for the preset time; when the microwave equipment starts to display the microwave power reading, use a demodulator to scan the optical fiber, continuously scanning and saving data during microwave heating. The specific method for calibrating the fiber optic temperature coefficient based on an infrared camera is as follows: Step S1: Prepare the complete rock sample, electromagnetic shielding material, computer, demodulator, infrared camera, optical fiber, shielding frame, shielding box, rectangular waveguide and surface radiator required for the calibration test, and determine the microwave power and heating time; Step S2: Connect the shielding box to the shielding frame, and place the infrared camera inside the shielding box to prevent microwave interference with the infrared camera; adjust the field of view of the infrared camera by changing the position of the shielding box to ensure that the microwave radiating surface is within the field of view of the infrared camera; mark the fiber optic temperature measurement section according to the size of the rock sample, and select an appropriate position on the surface of the rock sample to fix the fiber optic cable, which should be within the field of view of the infrared camera; extend the fiber optic cable out of the shielding frame and fix it to the ground; after the fiber optic cable is installed, connect one end of the rectangular waveguide to the microwave equipment and the other end to the surface radiator, with the surface radiator close to the rock surface to ensure that the infrared camera can monitor the rock surface temperature through the shielding box; Step S3: Fix the optical fiber, keeping it under slight tension, while ensuring that the optical fiber is in close contact with the rock sample surface; ensure that the optical fiber in the temperature measurement area is free from external obstructions, so that the infrared camera and the optical fiber can simultaneously monitor the surface temperature of the rock in the same area. Step S4: Calibrate the demodulator, connect the optical fiber to the demodulator, check and record the temperature coefficient of the optical fiber at this time; connect the infrared camera to the computer and use the infrared camera to record the initial temperature of the rock surface. Microwave heating is performed, and an infrared camera and optical fiber simultaneously monitor the temperature change at the same location. Step S5: Data processing, compare the temperature monitored by the infrared camera with the temperature change of the optical fiber at the same time and location, and correct the temperature coefficient; Step S6: Input the new temperature coefficient obtained in step S4 into the demodulator, and repeat the microwave heating experiment of steps S2-S4 n times. Compare the new temperature coefficients obtained in the n experiments. When the fluctuation of the new temperature coefficient is less than the set threshold, input the new temperature coefficient as the final fiber temperature coefficient into the demodulator. The specific method for step S5 is as follows: The temperature changes of both the infrared camera and the optical fiber at the same time were plotted using graphing software. The infrared monitoring temperature at different locations was divided by the optical fiber monitoring temperature, and the average of the results was calculated to obtain the optical fiber temperature correction coefficient. The optical fiber temperature correction coefficient was multiplied by the optical fiber monitoring temperature to obtain the corrected optical fiber monitoring temperature. The corrected optical fiber monitoring temperature was compared with the infrared monitoring temperature. When the temperature difference between the two methods at the same location does not exceed a set threshold range, the temperature overlap at that location is considered good. When the proportion of temperature points with good overlap exceeds the set threshold, the temperature correction coefficient is considered accurate. The temperature correction coefficient is then multiplied by the original optical fiber temperature coefficient to obtain the new temperature coefficient.

2. The method for real-time monitoring of rock internal temperature during microwave fracturing according to claim 1, characterized in that: The measuring hole is located near the heating hole, and the diameter of the measuring hole is between 1 and 1.5 cm, while keeping the wall of the measuring hole smooth.

3. The method for real-time monitoring of rock internal temperature during microwave fracturing according to claim 1, characterized in that: The method also includes a hollow fiber optic fixing tube installed on the side near the heating hole, with the fiber optic cable installed under the fixing tube to prevent the fiber optic cable from being squeezed by the thermal deformation of the rock during temperature measurement.

4. A method for real-time monitoring of rock internal temperature during microwave-induced fracturing, as described in claim 3, characterized in that: The fixed tube is composed of an arc-shaped tube and a soft plastic sheet, which are bonded together. Electromagnetic shielding material is installed on the fixed tube to prevent microwaves from passing through the fixed tube from another direction and heating the rock. The soft plastic sheet is connected to the wall of the measuring hole to prevent the fixed tube from moving.

5. A method for real-time monitoring of rock internal temperature during microwave-induced fracturing, as described in claim 4, characterized in that: The method involves pouring mortar into the measuring hole and then sealing the measuring hole with electromagnetic shielding material.

6. A method for real-time monitoring of rock internal temperature during microwave-induced fracturing, as described in claim 1, characterized in that: The method also detects whether the optical fiber is faulty before monitoring the temperature; the optical fiber is installed on the demodulator, and the demodulator is used to repeatedly scan the optical fiber in the absence of a heat source. The temperature change curve is close to 0, that is, there is no temperature change. Otherwise, the optical fiber has failed. Record the x-coordinate of the end of the optical fiber. During the installation process, continuously scan the optical fiber. When the x-coordinate of the end of the optical fiber changes, it indicates that the optical fiber has broken.

7. A method for real-time monitoring of rock internal temperature during microwave fracturing according to claim 1, characterized in that: The size of the rock sample must be greater than twice the depth of microwave penetration within it.

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